Ship construction



. J. McGRATH.

SHIP CONSTRUCTION.

APPLICATION FILED APR. Is, 1919.

2 SHEETS-SHEET l.

WITNESS IN V EN TOR.

JUJ77/V. M awr/z BY ATTORNEY-S l. McGRATH.

SHIP CONSTRUCTION.

APPLICATION man APR. 16, 191B.

1 ,3 1 4,069 Patented Aug. 26, 1919.

2 SHEETSSHEET 2.

I! .3. WITNESS INVENTOR.

A TTORNE Y S JUSTIN MGGRATH, OF SAN FRANCISCO, CALIFORNIA.

SHIP CONSTRUCTION.

Specification of Letters Patent.

Patented Aug. 26, 1919.

Application filed April 16, 1918. Serial No. 228,941.

To all whom it may concern Be it known that I, JUSTIN MCGRATH, a citizen of the United States, and a resident of the city and county of San Francisco and State of California, have invented certain new and useful Ship Construction, of which the following is a specification.

The invention relates to a combination steel and concrete ship, the bottom being of steel and the sides of reinforced concrete.

An object of the invention is to provide novelcomposite ship construction in which the steel portions of the hull are so arranged and constructed that an effective reliable and relatively strong reinforcing and anchoring of the concrete portions of the ship with the metal portions is provided.

Another object of the invention is to reduce the number of parts in constructing composite ships of the character described without detracting from durability and strength and to provide for rapid construction.

A further object of the invention is to provide a novel effective and easily constructed means for securely joining or uniting the concrete sides of the ship at the bilge with the steel bottom.

The invention possesses other advantageous features, some of which, with the foregoing, will be set forth at len h in the following description, where I s all outline in full, that form of the invention which I have selected for illustration in the drawings accompanying and forming part of the present specification. In said drawings I have shown one specific form of the hull of my invention, but it is to be understood that I do not limit myself to such form, since the invention, as expressed in the claims, may be embodied in a plurality of forms.

Referring to said drawings:

Figure 1 is a side elevation of the hull of my invention.

Fig. 2 is a side elevation of a portion of the hull before the concrete and the reinforcing is placed, showing the steel framing.

Fig. 3 is a half midship section of the hull of my invention.

In accordance with my invention I form the hull of a steel frame, cover the bottom of the hull with steel plates which preferably extend upward for a short distance, on the side of the hull, and form the sides of the hull of reinforced concrete. The bow and the stern of the hull are also preferably constructed of steel plates. The skeleton of the hull is formed of steel shapes suitably spaced and arranged to withstand the strains to which the hull is subjected. The bottom framing may consist of channels or angles 3, to the upwardly extending end portions 3 of which the ribs 4:, which are preferably formed of channels, are secured. The bottom is covered with steel plates 5, riveted to the framing, and these plates extend upward for a short distance on the sides of the hull, preferably to the top of the bilge. Secured to the ribs 4: at the inside of the hull at the bilge is an inner late 6, which forms with the outer bilge p ates a pocket into which the concrete is subsequently poured. Those of the plates 5 which curve upwardly at the bilge are secured to the plates 6 by bolts 9 which lie within the pocket and form an anchorage for the concrete which is poured therein and also stiffen the hull at the knuckle. Reinforcing material is arranged in the pocket and between the ribs, and the skeleton side of the hull is inclosed in suitable forms and the concrete is poured. The knuckle pocket forms an anchorage for the concrete in the steel bottom and the ribs, which are riveted to the steel bottom, support and reinforce the concrete sides.

At the bottom of the bilge, the reinforced concrete bottom 7 is raised above the steel bottom 5 and the hull is stiffened longitudinally by reinforced concrete beams 8 connecting the steel bottom with the concrete bottom. By providing a steel bottom for the hull, which is spaced from the reinforced concrete bottom and which is connected thereto at the sides by reinforced concrete beams, a full double bottom hull is provided, with the steel arranged to take up the strains due to grounding.

The decks 10 are preferably of reinforced concrete beams and slabs formed integral with the ships sides and are supported between the sides with reinforced concrete columns 12, which are placed along the longitudinal beams 8, thereby lending strength to the entire hull.

By this construction, a hull having a smooth steel bottom is provided, which offers less resistance to propulsion than a full concrete hull. By employing concrete sides and concrete beams, to withstand the strains to which the hull is subjected, the amount of steel entering into the construction of the hull is greatly decreased and the employment of specially fabricated steel shapes'is to a large extent eliminated. This construction lends itself to the rapid construction of hulls, possessing all of the advantages of steel hulls With the use of only asmall proportion of the steel used in steel hulls and involves the nseiof-vonly about one-third as many steel plates as are required ta .steellzt'ull.

"1. A rship having a "steel frame, :a bottom plating of steel, spaced inner and outer .zkmicklewplates at sides :of the bilge forming pockets and'reinforced concrete sides extend-- ing into said pockets.

, v2. A bull comprising a steel frame, steel plates covering the bottom 'of said :fr ame, T6-

inforced concrete covering the sides of said frame and a reinforced concrete bottom spaced abovesaid plates and integral with said sides. V

. 3. A v-hu ljl comprising steel frame, steel I plates covering the bottom of said frame, ;a

it crete bottom,

I'GlIDfQ'lGBCl concrete wbottom spaced above 'TSEUlGl steel plates and longitudinalb disposed reinforced concrete beams connecting :the bottom of said f rameiand said-con- Copies of :this patent may {be obtaineiddfor five cents ,each ,7=b Washington, .D. 0.

I 4. A hull having a steel bottom, a rein: forced concrete bottom spaced above said steel bottom "andlongitudinal beams connecting said bottoms.

5. A hull comprising a steel frame, steel plates covering the bottom of said frame,

reinforced concrete Walls covering the sides of said frame, a reinforced concrete deck formed integral With said Walls, a min forced concrete :bottom spaced above said plates and integral With said walls, longitudinal reinforced concrete beams connecting the steel bottom with the concrete bottom and reinforced concrete deck supporting col V MGGRATH.

y addressing the t-Commissioner of Patents, i 

